EM Fixtures

[Alwayslearningelec]

I have em fixtures that are being fed from an em panel which is backed up by a generator. There is a note on the drawings that say " all em fixtures labeled em, all fixtures used as night light and exits shall be cicuited unswitched".

Actaully most of my em fixtures are being feed with two circuits, one em and one normal. There are "ELR"( emergency lighting relays) in a lot of areas. It says provide ELR to bnypass local switching when utily power is lost. I guess this is because they want the ability to switch the em lights but that conflicts with the note above. I guess.


1. I did not get any fixtures quoted as em from my vendors. I just assumed an em circuit means no batery pack etc. I hope I did not drop the ball there. I see nothing anywhere about battery back up. How do you interpret this?

Thanks.

 

[Greg Swartz]

Blueprints...

Blueprints...

When I look at the prints, specifically the fixture schedule, there will be a list of all types of fixtures required on the job.

If you have a type "EM" somewhere, look at the part number. If it is different than the non-EM type, then, I'd order that part... no matter what I interpreted.

From your description, it sounds like the EM fixtures (half shaded? lightly shaded? half black?) need a battery pack since they are fed from the EM panel and the EM panel is backed up by a generator. The generator is going to take up to 1 minute to turn on.

You stated that they are fed from 2 sources. That would make the ones fed with 2 sources, normally switched, and fed with backup power. The nice battery packs have 2 power leads already hooked up for this purpose.

The other possibility is an unswitched from the same main circuit as the rest of the lights, but with the emergency backup. Again, having a battery pack here is of use, since the generator may take up to 1 minute to turn on.

Of course, all this is moot if the EM panel has a UPS that holds the load for all these items and an ATS for when the generator kicks in.
If that is the case, then no battery packs should be required. However, then the double feed would be confusing.

 

[Alwayslearningelec]

When I look at the prints, specifically the fixture schedule, there will be a list of all types of fixtures required on the job.

If you have a type "EM" somewhere, look at the part number. If it is different than the non-EM type, then, I'd order that part... no matter what I interpreted.

From your description, it sounds like the EM fixtures (half shaded? lightly shaded? half black?) need a battery pack since they are fed from the EM panel and the EM panel is backed up by a generator. The generator is going to take up to 1 minute to turn on.

You stated that they are fed from 2 sources. That would make the ones fed with 2 sources, normally switched, and fed with backup power. The nice battery packs have 2 power leads already hooked up for this purpose.

The other possibility is an unswitched from the same main circuit as the rest of the lights, but with the emergency backup. Again, having a battery pack here is of use, since the generator may take up to 1 minute to turn on.

Of course, all this is moot if the EM panel has a UPS that holds the load for all these items and an ATS for when the generator kicks in.
If that is the case, then no battery packs should be required. However, then the double feed would be confusing.

Thanks, that was insightful. I think I need the em's.

 

[Alwayslearningelec]

The panels that are feeding the em's are being fed from an ATS's which is being feed from a normal and em switchboards. Isn't that the norm.? I just checked the riser. I did not do the feeder portion and the guy who I work with is kinda a jerk......

 

[infinity]

Typically night light [N/L] circuits are on 24 hours a day and are never switched. They can be backed up by a generator to also provide egress lighting. Sounds like the notes that you've posted contradict each other. Further information from the person who wrote them should be requested to find out how they intended for the system to work.

 

[Ragin Cajun]

You need these. Come in 3 and 20A versions.

You can turn the emergency light on and off with the rest of the lights but don't have to leave it on 24/7.


http://www.bodine.com/downloads/specs/GTD.spec.(std).L4100004.pdf

http://www.bodine.com/products/specs/gtd20a.html

RC

 

[Alwayslearningelec]

Thanks Rajin. I thing that's what the ELR that is shown on the drawings does.

 

[Alwayslearningelec]

But this device would have to be installed in every em fixture I gather. The Em fixtures come with a battery backup already installed so it is more work for the GLR........right?

 

[infinity]

There is a note on the drawings that say " all em fixtures labeled em, all fixtures used as night light and exits shall be cicuited unswitched".

I'm confused as to why you're installing ELR's for fixtures that are not supposed to be switched in the first place?

 

[Ragin Cajun]

But this device would have to be installed in every em fixture I gather. The Em fixtures come with a battery backup already installed so it is more work for the GLR........right?

Not so. There is a 20A model. The smaller one is fused at 3A so it can cover more than one fixture depending on load.